From ed74277bd80a47ec552ccf3581583421c3a4df5d Mon Sep 17 00:00:00 2001 From: Todd Poynor Date: Thu, 19 Jul 2018 20:49:16 -0700 Subject: staging: gasket: always allow root open for write Always allow root to open device for writing. Drop special-casing of ioctl permissions for root vs. owner. Convert to bool types as appropriate. Reported-by: Dmitry Torokhov Signed-off-by: Zhongze Hu Signed-off-by: Todd Poynor Signed-off-by: Greg Kroah-Hartman --- drivers/staging/gasket/gasket_core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'drivers/staging/gasket/gasket_core.c') diff --git a/drivers/staging/gasket/gasket_core.c b/drivers/staging/gasket/gasket_core.c index ba48a379b0ad..254fb392c05c 100644 --- a/drivers/staging/gasket/gasket_core.c +++ b/drivers/staging/gasket/gasket_core.c @@ -1072,6 +1072,7 @@ static int gasket_open(struct inode *inode, struct file *filp) char task_name[TASK_COMM_LEN]; struct gasket_cdev_info *dev_info = container_of(inode->i_cdev, struct gasket_cdev_info, cdev); + int is_root = capable(CAP_SYS_ADMIN); gasket_dev = dev_info->gasket_dev_ptr; driver_desc = gasket_dev->internal_desc->driver_desc; @@ -1085,7 +1086,7 @@ static int gasket_open(struct inode *inode, struct file *filp) "Attempting to open with tgid %u (%s) (f_mode: 0%03o, " "fmode_write: %d is_root: %u)", current->tgid, task_name, filp->f_mode, - (filp->f_mode & FMODE_WRITE), capable(CAP_SYS_ADMIN)); + (filp->f_mode & FMODE_WRITE), is_root); /* Always allow non-writing accesses. */ if (!(filp->f_mode & FMODE_WRITE)) { @@ -1099,8 +1100,9 @@ static int gasket_open(struct inode *inode, struct file *filp) gasket_dev, "Current owner open count (owning tgid %u): %d.", ownership->owner, ownership->write_open_count); - /* Opening a node owned by another TGID is an error (even root.) */ - if (ownership->is_owned && ownership->owner != current->tgid) { + /* Opening a node owned by another TGID is an error (unless root) */ + if (ownership->is_owned && ownership->owner != current->tgid && + !is_root) { gasket_log_error( gasket_dev, "Process %u is opening a node held by %u.", -- cgit v1.2.3-55-g7522